Activity on the World Wide Web (“Web”) involves heterogeneous entities such as end users, web pages, search queries, and keywords. These entities may be referred to in the search context as objects. The objects may be interrelated by virtue of having similar content or by some other relationship. Traditional searches performed using search engines, such as commercial web search engines, generally deal with single types of objects, such as web pages or documents.
Most of these traditional search services generally take a search query as input from a user and display a ranked list of web pages as a search result. However, the user may desire more robust information such as a list of possible words that may be used to refine the submitted query for more accurate results, a list of users who have searched for the same keyword, and even web pages related to a specific web page. Only searching single types of objects tends to limit the information provided to the end user and, therefore, reduces the accuracy and value of the search results.